Mexico wants more than just a presidential decree on its genetically modified corn ban in place as it enters the final phase of a dispute with the U.S., so the country is working to solidify the prohibition in its national food production standards.

Mexico unveiled a revised draft of its standard for making corn dough for tortillas and tostadas in June to include the stipulation that it is illegal for tortilla makers to use dough made from GM white corn – about four months after Mexican President Andrés Manuel López Obrador unveiled a decree that does the same.

Entrenching a controversial rule or regulation into a country’s domestic standards is common practice when international opposition is expected, according to an industry source who asked not to be named because they are not authorized to speak on the subject.

“It’s a lot harder to change than a presidential decree that can be rescinded,” the source said. “It’s a formal regulation. It has the same impact as a presidential decree, but it makes it a lot more embedded in Mexico’s regulatory system.”

Mexico has made clear the ease with which it can rescind presidential decrees. It did so on Feb. 13 when it unveiled a new decree on ridding the country of GM corn that prohibited “the use of genetically modified maize grain for food” and ordered “the gradual substitution in the country of genetically modified maize for animal feed and industrial use for human food.” This new decree supplanted a previous decree issued in December 2020 that failed to differentiate between food-grade and feed corn.

The U.S. did not challenge Mexico’s 2020 presidential decree, but it is standing up to the latest version. 

The Biden administration is challenging Mexico’s GM corn ban under the U.S.-Mexico-Canada Agreement. The U.S. ended months of consultations and called for a dispute panel on Aug. 17.

“The United States has used the tools provided by the USMCA in attempting to resolve concerns with Mexico’s biotechnology measures,” U.S. Trade Representative Katherine Tai said in a statement at the time. “Today, the United States is taking the next step in enforcing Mexico’s obligations under the USMCA.”

AP_Dec_22_Katherine_Tai_2.jpgUSTR Katherine Tai (AP Photo/Paul Sancya)

But Mexico was already working to establish the prohibition against GM corn and then, on July 28, the country took the added step of submitting the newly drafted standard to the World Trade Organization’s Technical Barriers to Trade Committee.

Mexican officials have consistently argued the country’s ban on GM corn in tortillas is not a trade issue, despite the fact that importers have been purchasing food-grade corn from U.S. farmers for years.

Mexican Undersecretary for Foreign Trade Alejandro Encinas, in a recent letter to USTR officials, said the ban does not affect “trade or imports since, among, other reasons, Mexico is self-sufficient in the production of GM-free white corn. What this is about is consolidating … sovereignty and food security in relation to a staple product in the culture of Mexicans.”

Furthermore, Encinas, in a separate response to U.S. questioning over the country’s anti-GM stance, stressed Mexico is simply protecting its native, non-GM corn in order to “preserve self-sufficiency, cultural identity, the biocultural wealth of farming communities and the Mexican gastronomic heritage.”

While Mexico’s submission of the proposed tortilla-making standard – it goes by the technical name domestically as NOM-187 – to the WTO’s Technical Barriers to Trade Committee may be an admission that trade will be impacted, it does so in a way that would give the country international cover for its actions.

Don't miss a beat! Sign up for a FREE month of Agri-Pulse news! For the latest on what’s happening in agriculture in Washington, D.C. and around the country, click here.

“It’s just saying that Mexico is going to make this a standard for tortilla production,” said Joe Glauber, a senior research fellow at the International Food Policy Research Institute and former USDA chief economist. “It meets WTO guidelines in the sense that it says any tortillas made in Mexico have to be from non-GMO corn. It essentially says, ‘We’re not discriminating against the U.S. We’re saying this applies to anybody.’”

Joe-Glauber.jpgJoe Glauber, IFPRI

WTO rules specify that countries can’t hold foreign imports to different standards than domestically made products.

“It gets Mexico away from the national treatment issue in the sense that it’s not discriminatory against foreign suppliers because they’re being treated the same way domestic suppliers are,” Glauber said.

The WTO stresses that its national treatment principle – essentially “giving others the same treatment as one’s own nationals” – is present in all three of the organization’s main agreements.

But the U.S. had already responded to Mexico’s redrafted NOM-187 standard for tortilla making even before the country submitted it to the WTO, according to a document posted online by the Mexican government.

Mexico, the U.S. says in the document, admits in NOM-187 that the standard’s GM prohibition “is not equivalent to any international standard” and that’s a problem when it comes to the USMCA.

“The United States is concerned that this measure is not based on science and threatens to disrupt trade,” the U.S. wrote in a submission to the Mexican government. “Mexico asserts … that this draft NOM does not conform to an international standard because none exists.”

Mexico, the U.S. says, doesn’t have any scientific research to back up its claims that GM corn is a health risk and that means the tortilla-making standard – like the presidential decree – is a violation of the USMCA trade pact.

For more news, go to